Operator for counterbalanced elevator doors



R. s. PEELLE 1,864,667

OPERATOR FOR COUNTERBALANCED ELEVATOR DOORS June 28, 1932.

Filed April 5, 1930 .3 Sheets-Sheet l A TToRNEY R. s. PEELLE 1,864,667

OPERATOR FOR COUNTERBALANCED ELEVATOR DOORS June 28, 1932.

Filed April 5, 1930 5 Sheets-Sheet 2 INVENTOR ATTORNEY.

June 28, 1932. s, PEELLE 1,864,667

OPERATOR FOR COUNTERBALANCED ELEVATOR DOORS Filed April 5, 1950 5 Sheets-Sheet 5 'INVENTOR W/WW ATTORNEY Patented June 28, 1932 UNITED STATES PATENT OFFICE ROBERT'S. PEELLE, OF HOLLIS, NEW YORK, 'ASSIGN OR TO THE PEELLE COMPANY, 01 BROOKLYN, NEW YORK, A CORPORATION OF NEW YORK OPERATOR FOR GOUNTERBALANCED ELEVATOR DOORS Application filed April 5, 1930- Serial No. 441,819.

My invention relates to operators for counterbalanced elevator doors, and more, particularly to an operator of the type in which each door in an elevator shaft may be opened 5 or closed by means of an electric motor located within the shaft, means being provided whereby an electric current from a source 15 wall of the shaft adjacent the door openings,

flexible connections extending from one of these sections to the other and passing over sheaves adjacent the lintel of the door opening and secured to the guide rail structure. The space available adjacent the shaft for the installation of such doors amounts only to a few inches, and the conditions within an elevator shaft make the installation of the doors diflicult and expensive since the door equipment must be adapted to the requirements of the elevator car and the structure within the shaft incidental to its operation.

In the installation of elevator door equipments, the guide structure is produced in the factory with the sheaves, tracks, stops, etc., completely and permanently assembled therein. The uide rails are bolted to the wall of the shai t, the section of the rail adj acent each opening being accurately positioned in relation to the sill of the opening by means of certain guide markings upon the rail structure.

Counterbalanced elevator doors of the type to which my invention relates, vary widely in their construction to meet the requirements of the conditions of an elevator shaft. The ordinary standard counterbalanced door is used in openings in which the distance between the sill of one opening and the lintel of an adjacent opening is greater than the height of either of the door sections. Where the distance is less than this, what is known as a pass type door is used, since with this type of door the space required for its opera- 4 tion, between the sill and lintel of adjacent openings, need not be more than 18 or 20 inches. When the available space between the sill and the lintel of the opening below is less than that which will permit the use of the ordinary pass type door, it is the practice to use what is known as a self-sealing pass type door, since this type of door may be used where the available space is as low as 14 inches.

I have heretofore devised an operator employmg electric motor actuated means adjacent each door in a shaft, and a remote control mechanism common to all of the motors in a shaft by which the motors may be selectively energized and be made operative only when a car is at the opening closed by the selected door.

In this type of door operator, the construction is such that the motor and the power transmitting means may be permanently connected with the rail structure in the shop so as to permit the installation of the operator while installing the guide rail structure, and avoid all of the labor and expense incidental to the assembling and installing of the operator independently of the guide rail structure. In this type of operator, each motor transmits power to a sheave, and the construction of sheave and flexible connections is such as to permit the manual opening or closing of any door in the event of a failure of power or damage to the operator.

With the above conditions in mind, the object of my present invention is to provide, in the type of operator above referred to, a construction and arrangement of the motor and the mechanism for transmitting power therefrom to the sheave which will permit the employment of the same operator construction with any type of elevator door, irrespective of the space between the sill of one opening and the lintel of the opening below.

By this construction I not only secure all of the advantages, so far as low H. P., speed of movement of the door sections, and compactness of parts incidental to the type to which the invention relates, but I am enabled to provide a standard operator construction applicable to counterbalanced doors of any construction and of practically any size, since weight, and the power required of the motor p in weig .tric motor secured to said gui within the shaft and below a sheave, a gear carried by the shaft of said motor, a shaft suflicient to overcome any difference t between the two sections, which is never great.

The invention consists rimarily in an operator for counterbalanced elevator doors embod 'ng therein the combination with a guid e rail structure within an elevator shaft, 9. series of elevator doors each having sections vertically and oppositely movable on said structure, connections between said sections on the opposite sides thereof, and sheaves about which said connections fess, of an'elece rail structure is merellyl counter to the shaft of said motor carrying a large ear enmeshed with the gear upon the motor s aft, and a small sprocket wheel, a sprocket wheel of substantially the diameter of a sheave secured thereto, a sprocket chain co-operating with said sprocket wheels, a main electric power line extending adjacent all of said doors, a branch line extending therefrom adjacent each door and connected with the motor adjacent such door, a normally open switch in each of said branch lines adapted to be operated only when a car is positioned adjacent said switch, means carried by and movable with an elevator car cooperating with the switch in any branch line, pole changing switches contro ling the circuits to said main ower line, electro-magnetic control mechanisms for said pole changing switches, and means whereby said control mechanisms may be selectively actuated from a remote point; and in such other novel features of construction and combination of parts as are hereinafter set forth and described, and more particularly pointed out in the claims hereto appended.

Referring to the drawings,

Fig. 1 is a view of two counterbalanced elevator doors at adjacent door openings in a shaft, each door being equipped with anoperator embodying the invention, said view being vertically and horizontally condensed;

Fig. 2 is a front elevation upon a larger scale showing the arrangement of the motor of the operator in relation to the guide rail structure and the sheave, and the power transmitting mechanism between the motor and the sheave;

Fig. 3 is a view thereof from the right of Fig. 2;

Fig. 4 is a plan view thereof; and

Fig. 5 is a diagrammatic showing of one form of electrical control system capable of use with the operator of my invention.

I i. Mi-.11... Mm,

parts through- "is shown in the drawings, although as heretofore stated, the construct-ion and arrangement of parts of the operator are such as to permit of their application to any construction of counterbalanced door, irrespective of the available space between the lintel of one opening and the sill of the opening above.

In the drawings, the upper door section is shown at 10, the lower section at 11 and the chains or other flexible connections secured adjacent the bottom of the section 10" and the top of the section 11, at 12. Each of these chains 12 passes over a sheave 13 lo cated above the upper door section and, as will more fully appear hereinafter, secured to the guide rail structure. One end of each chain 12 is connected in the usual manner to a hanger bar 14 forming a part of the top bar structure of the lower section 11.

The sections 10 and 11 are slidable upon tracks 15 forming a part of the guide structure, such tracks usually being carried by what is known as a wall angle 16, one flange of which is adapted to be bolted to the wall of the building, and the other flange of which extends inwardly of the shaft. This guide rail structure usually extends throughout the entire height of the shaft in operative relation to all of the doors in the shaft. Its details may be varied according to the detailed construction or type of the door itself. Secured to the guide rail structure, at opposite sides of each door opening, are adjustable stops 17, so positioned in relation to the sill of a door opening as to bring the top bar of the lower section at rest on substantially the plane of the sill of the door-opening.

Also co-operating with the hanger bar 14 are-lock members 18 of an old and well known construction.

The features above referred to are all old and well known in the freight elevator door art, and are herein shown and described as typical of a door having those characteristics which present the problems necessary to be solved by the application of a motor actuated operator thereto. The same characteristics are found in doors to which other types of operators are applied.

The above description is limited to those structural characteristics of the door necessary to an understanding of the operation of the operator of my invention and of the doors equipped therewith. Consequently, other details of the door structure and of the various mechanisms referred to will not be de-.

scribed.

In the operation of my invention shown in the drawings, the power from the motor is applied only to one of the sheaves 13, the other sheave, that shown at' the left of Fig. 1, being of the usual and well known construction. This application of power to only one sheave is permissible with counterbalanced doors of narrower widths, although with heavier and wider doors the operator mechanism may be duplicated upon opposite sides of the door.

In the embodiment of the invention shown in the drawings, I provide a frame having a narrow base 19 on the upper part of which is formed a sheave housing 20 in which the sheave 13 is mounted by means of the shaft 21. The lower art of the frame is provided with an 0 set downwardly presented support 22, reinforced by a suitable fillet 23 and provided with a bearing web 24 adjacent said fillet. The base 19 is securedto the guide rail structure preferably by means of bolts, with the portion thereof forming the sheave housing extended beyond the edge of the guide rail structure a distance suflicient to afford the proper clearance for the run of the flexible connections 12 between the two door sections, thus avoiding an cutting of the guide rail structure or the nwardly directed flange of the wall angle forming a part thereof.

Positioned below the offset support 22, and secured thereto and to the guide rail structure is a narrow high-torque motor 25, the detailed construction of which need not be described since this will be made the subject matter of a separate application for patent. Suffice it to say that this type of motor is one which was developed especially for the operator of the invention, wherein the duration of the operation of the motor is measured by seconds, so that the tendency of a hightorque motor to overheat is no factor. By employing such a motor, however, I am enabled to get the desired H. P. rating in very small compass, and to rovide a detailed construction which especially adapts it to the character of work for which the motor is designed. The motor is narrow and fiat as shown, having a shaft 26 carrying a small spur gear 27. The motor and the gear are positioned, in their entirety, within the vertical plane of the sheave housing 20.

The motor 25 is provided with base lugs 28, bolted or otherwise secured to the guide rail structure, and with head lugs 29 bolted or otherwise secured to the support 22.

Mounted in the bearing web 24 is a shaft 30, counter to the shaft 26. Carried by this shaft is a large spur gear 31, enmeshed with, the small motor gear 27, and a small sprocket wheel 32, the gear 31 being positioned upon one side of the web 24, and the sprocket wheel 32 being positioned upon the other side thereof. The sheave 13 has secured thereto a large sprocket wheel 33 which forms oneshroud of the sheave, and is positioned upon the side thereof toward the wall of the shaft and properly lined up with the sprocket wheel 32. A sprocket chain 34 co-operates with said sprocket wheels respectively.

The base 19 of the operator frame is provided with an elongated 0 ening 35 extending from adjacent the sha t 30 to the bottom of the sheave housing 20 for affording clearance for the run of the chain 34, one reach of which is positioned upon one side of the base 19, and the other reach of which is positioned upon the other side of said base, although no cutting of the guide rail structure is necessary to secure such clearance.

It will be noted that the operator of the invention, whether it be applied to a standard counterbalanced door structure or to a pass type door structure, has the sheave 13 located according to the requirements of the type of door to which the operator is applied, and that the motor 25 with its gearing and chain and sprocket mechanism connecting same with the sheave 13 is located below the sheave, thus adapting the operator to any type of door since an adequate space is al ways available below the sheave irrespective of the clearance represented by the space betweenthe lintel of one door opening and the sill of the opening above, or above the sheave.

With the construction herein described, the operator motor and its appurtenances are contained, in their entirety, within the space between thesheave housin and the wall of the shaft, which space is determined by the requirements of the guide rail structure. Consequently, under no circumstances will any modification of the plans for the elevator equipment be required to permit of the installation of the operator.

In connection with the operator mechanism above described, it is essential to provide an electrical control mechanism by which any motor 25 in a shaft may have power applied thereto to turn it in either direction and thus apply either openin or closing movement to the door. The speci c arrangement of such a control mechanism forms no part of my present invention, although its use is essential to a successful use of the operator.

' I have shown in Fig. 5 of the drawings, a diagram illustrating an electrical control device capable of use with the other characteristics of the operator shown, this being a remote control including a pole changing switch mechanism 36 in the main line supplying power to any motor 25 in a shaft. I

also provide in this control mechanism a time limit switch 37, by which the duration of the actuation of the motor is determined. At 38 I have shown an ordinary car switch mechanism controlling the circuits from the source 39 to the holding magnets 40 and 41 of the pole changing mechanism 36. At 42 I have illustrated a shaft switch mechanism adapted to be actuated by a cam 43 carried by the elevator car and controlling the circuit from the main electric power line 44 to the motor 25. There is a shaft switch 42 adjacent each door opening in a shaft which controls a branch circuit 45 to the motor 25 of the operator for the door at such opening.

This circuit control mechanism is capable of various refinements, a description of which is unnecessary to an understanding of the present invention, which relates more particularly to the use, in a counterbalanced door operator, of a particular construction of motor actuated power transmitting means, the current to the motor of which is under the influence of a remote control mechanism of the general type above described.

The operation of the herein described operator is substantially as follows Under normal operating conditions, ad doors in a shaft are closed, and it is essential that a car be located at some particular opening before the door at that opening can be actuated by the operator of the invention. This is controlled by the shaft switch 42 and the car cam 43. The actuation of the switch 42, however, merely permits the application of power to the motor, and its actuation alone merely establishes a condition by which other controls may be set so as to complete the circuit through this switch to the motor 25.

When a car is brought to rest at a door opening, the operator actuates the car switch 38, thus closing the circuit through the time limit switch 37 to the holding magnet 40 of the mechanism 36. The energizing of this magnet closes a circuit from the source 39 to the main line 44, thus completing the circuit to the motor 25. When power is applied to this motor, it is transmitted through the small gear 27 upon the motor shaft to the large gear 31 upon the counter shaft 30, which shaft also carries the sprocket 32. The turning of the s rocket wheel 32 transmits power through the chain 34 to the large sprocket wheel 33 carried by and rotatable with the sheave 13, thus turning this sheave at a low speed compared with the motor speed, but at a speed sufiiciently high to ensure a rapid opening movement of the door.

By using a high-torque motor 25, I secure high efficiency in the motor operation by a mechanism occupying verp; little space. The duration of the run of t e motor, whether controlled by a constant pressure switch to effect either the opening or the closing of the door, is so short as to preclude any possibility of the overheating of the motor, notwithstanding that its design is such as would, for ordinary purposes, preclude its use.

By locating the motor, the gear 31 and the wheel 32 below the sheave, this mechanism may be applied to any construction of counterbalanced elevator door without regard to the distance between the sill of one opening and the lintel of the opening below. It is located in its entirety between the sill and the lintel of a door opening, so that when assembling the guide rail structure in the factory, it is merely necessary to properly locate the sheave 13 in relation to the guide rail structure to meet the requirements of the type of door to be used. Consequently, so far as the door installation and construction is concerncd, the presence of the operator has no influence whatever.

The chain 12 or other flexible connection merely frictionally engages the sheave 13, and the results secured by the construction herein described arise solely from the fact that the two sections 10 and 11 of the door have a counterbalancing action one on the other, so that the load upon the motor is so small as to permit the utilization of a motor of low H. P. and of small dimensions. The doors themselves may weigh from four to five hundred pounds, or even more, and yet the motor 25 has only a fraction of a H. P. and its overall dimensions may be only a few inches.

The frictional engagement between the chains 12 and the sheaves 13 is not essential, so far as the application of power for opening or closing the door is concerned, but this frictional engagement introduces two very desirable functions in the operator, the first of which is to supplement the action of the time limit switch in preventing injury to the door or operator structure as a result of overrunning of the motor upon the completi on of either the opening or the closing movement of the door. This is of minor im ortance, however, since the time limit switch may be so set as to cut off the power to the motor before the door has reached either the fully opened or the fully closed position, the moving inertia of the counterbalanced door sections completing either the opening or the closing movement without the application of power thereto.

In the event of the failure of the time limit switch, however, the engagement of the hanger bar 14 on the lower door section with the stops 17 relieves the chain upon one side of the sheave and connected with said hanger bar, from the load of this section and'causes slippage of the sheave in relation to the chains, notwithstanding the continued application of power to the sheave. This, however, is a mere precautionary feature.

When the two sections come together upon the closing movement, the same slippage will occur since the chain upon the other side of the sheave will be relieved of the load of the upper section.

The main advantage of the frictional engagement between the chains and the motor actuated sheave, is that in the event of the failure of any motor from any reason whatsoever, the door may still be operated manually, the chain either having slippage in relation to its sheave, or actuating the speed reducing mechanism and the motor so as to permit the free opening or closing movement of the door.

Because of this condition, no interruption of the elevator service need result from the 34 failure of the operator as to any door in the shaft, and the failure of any one operator will not require any servicing as to any of the other operators. If the trouble be in the remote controls, the only servicing required is as to that control, and during such servicing the elevator service may be maintained and access may be had therefrom to any floor of the building by the manual actuation of the doors. L

By reason of this capability of the operator, none of the clutch or other mechanisms, usually provided for the purpose of permitting the operator to be made inoperative in relation to all of the doors in a shaft, is required.

The locking members 18, whether in the form shown in the invention, or in any other desired form, are employed to'prevent the opening of a door from the floor side of a shaft at all times excepting when an elevator car is opposite the opening closed by the door to be opened, and hence these locks cooperate with the operator of the invention in preventing manual operation of the doors from the floor of a building which, except for such locks, might be possible with the construction of operator described.

As stated above, the time limit switch controls the circuit to the holding magnet for a predetermined interval at the expiration of which the circuit to the motor will be automatically interrupted by this switch. The time limit switch is included only in the circuit closed for the purpose of openin the door, the switch mechanism for app ying power to the motor for closing the door being a positive pressure switch, or one in which the operator must maintain the switch in the closed position during the full closing movement of the door excepting for that movement as a result of the moving inertia of the two sections above referred to.

The manner of supporting the motor, the speed reducing power transmission gearing and the sheave, by, and in a predetermined relation to, the guide rail structure, are matters of primary importance, and as this has been heretofore pointed out, it is desired to merely add that the construction and arrangement of parts herein referred to, is such as to, secure a ratio of speed of the sheave and of the motor shaft to impart the desired rate of travel of the door section during the opening and closing of the door, by a mechanism located in its entirety within the limited space available, and without any modification whatever in the guide rail or the door structure excepting the addition to the sheave 13 of the sprocket wheel 33, the use of a special form of frame 19 including therein the sheave housing 20, the support 22, the web 24 and the slot 36 in the frame 19 affording clearance for the run of the chain It is not my intention to limit the invention to the precise details of construction shown in the drawings it being apparent that such ma be varie without departing from the spirit and scope of the invention.

While in the drawings, I have shown the use of a single motor operative upon one sheave only, it is obvious that this mechanism may be duplicated upon opposite sides of the door if desired. 1

Having described the invention, what I claim as new and desire to have protected by Letters Patent, is

1. An operator for counterbalanced elevator doors embodying therein the combination with a guide ra1l structure within an elevator shaft, a series of elevator doors each having sections vertically and oppositely movable on said structure, connections between said sections on the opposite sides thereof, and sheaves about which said connections pass, of an electric motor secured to said guide rail structure within the shaft and be low a sheave, a gear carried by the shaft of said motor, a shaft counter to the shaft of said motor carrying a large gear enmeshed with the gear upon the motor shaft, and a small sprocket wheel, a sprocket wheel of substantially the diameter of a sheave secured thereto, a sprocket chain co-operating with said sprocket wheels, a main electric power line extending adjacent all of said doors, a branch line extending therefrom adjacent each door and connected with the motor adjacent such door, a normally open switch in each of said branch lines adapted to be operated only when a car is positioned adjacent said switch, means carried by and movable with an elevator car cooperating with the switch in any branch line, pole changing switches controlling the circuits to said main power line, electro-magnetic control mechanisms for said pole changing switches, and means whereby said control mechanisms may be selectively actuated from a remote point.

2. An operator for counterbalanced elehaving sections vertically and oppositely ter to the shaft of said motor mounted in said web, a large gear carried by said shaft upon one side of said web and enmeshed with the gear upon the motor shaft, and a small sprocket wheel also carried by said shaft and positioned upon the other side of said web, a sprocket wheel of substantially the diameter of a sheave secured thereto, a sprocket chain co-operating with said sprocket wheels, 2. main electric power line extending adjacent all of said doors, a branch line extending therefrom adjacent each door and connected with the motor adjacent such door, anormali on ly open switch in each of said branch lines adapted to be operated only when a car is posltioned adjacentsaid switch, means carried by and movable with an elevator car cooperating with the switch in any branch line, pole changing switches controlling the circuits to said main power line, electro-magnetic control mechanisms'f r said pole chang-' ing switches, and means ihereby said control mechanisms may be selectively actuated from a remote point.

3. An operator for counterbalanced elevator doors embodying therein the combination with a guide rail structure within an elevator shaft, a series of elevator doors each having sections vertically and oppositely movable on said structure, connections between said sections on the opposite sides thereof, and sheaves about which said connections pass, of a frame having a narrow base secured to the guide rail structure, a sheave housing formed adjacent the upper part of said base for receiving said sheave, an offset downwardly presented support toward the bottom thereof, and a bearing web extending from adjacent said housing to adjacent said support, an electric motor positioned below and secured thereto, a gear carried by the shaft of said motor, a shaft counter to the shaft of said motor mounted in said web, a large gear carried by said shaft upon one side of said web and enmeshed with the gear upon the motor shaft, and a small sprocket wheel also carried by said shaft and positioned upon the other side of said web, a sprocket wheel of substantially the diameter of a sheave secured thereto, a sprocket chain 1 co-operating with said sprocket wheels, said frame having a slotted opening adj acen said web to afford clearance for the run of aid sprocket chain, a main electric power line extending adjacent all of said doors, a branch line extendin therefrom adjacent each door and connected with the motor adjacent such door, a normall open switch in each of said branch lines a apted to be operated only when a car is (positioned adjacent said switch, means carrie by and movable with an e-levator car co-operating with the "switch in any branch line, pole changing switches controlling the circuits to said main power line electro-magnetic control mechanisms for said pole changing switches, and means whereby said control mechanisms may be selectively actuated from a remote point.

4. An operator for counteibalanced elevator doors embodying therein the combination with a guide rail structure within an elevator shaft, a series of elevator doors each having sections vertically and oppositely movable on said structure, connections between said sections on the opposite sides thereof, and sheavesabout which said connections pass, of a narrow high-torque electric motor secured to said guide rail structure within the shaft and below a sheave, a gear carried by the shaft of said motor, a shaft counter to the shaft of said motor carrying a large gear enmeshed with the gear upon the motor shaft, and a small sprocket wheel, a sprocket wheel of substantially the diameter of a sheave secured thereto, a sprocket chain co-operating with said sprocket wheels, said motor, said gears, said sprocket wheels and said chain all being positioned in their entirety within the space between the vertical plane of said sheave and the wall of the shaft, a main electric power line extending adjacent all of said doors, a branch line extending therefrom adjacent each door and connected with the motor adjacent such door, a normally open switch in each of said branch lines adapted to be operated only when a car i positioned adjacent said switch, means carried by and movable with an elevator car cooperating with the switch in any branch line, pole changing switches controlling the circuits to said main power line, electro-magnetic control mechanisms. for 581d pole changing switches, and means whereby said control mechanisms may be selectively actuated from a remote point.

5. An operator for counterbalanced elevator doors embodying therein the combination with a guide rail structure within an elevator shaft, a series of elevator doors each having sections vertically and oppositely movable on said structure, connections between said sections on the opposite sides thereof, and sheaves about which said connections pass, of a frame having a narrow base secured to the guide rail structure, a sheave housing formed adjacent the upper part of said base for receiving said sheave, an offset downwardly presented support toward the bottom thereof, and a bearing web extending from adjacent said housing to adjacent said support, a narrow high-torque electric motor positioned below and secured thereto, a gear carried by the shaft of said motor, a shaft counter to the shaft of said motor mounted in said web, a large gear carried by said shaft upon one side of said web and enmeshed with the gear upon the motor shaft, and a small sprocket wheel also carried by said shaft and positioned upon the other side of said web, a sprocket wheel of substantially the diameter of a sheave secured thereto, a sprocket chain co-operating with said sprocket wheels, said motor and said gears being positioned in their entirety within the space between the vertical plane of said sheave housing and the wall of the shaft, a main electric power line extending adjacent all of said doors, a branch line extending therefrom adjacent each door and connected with the motor adjacent such door, a normally open switch in each of said branch lines adapted to be operated only when a car is positioned adjacent said switch, means carried by and movable with an elevator car cooperating with the switch in any branch line, pole changing switches controlling the circuits to said main power line, electro-magnetic control mechanisms for said pole changing switches, and means whereby said control mechanisms may be selectively actuated from a remote point.

6. An operator for counterbalanced elevator doors embodying therein the combination with a guide rail structure within an elevator shaft, a series of elevator doors each having sections vertically and oppositely movable on said structure, connections between said sections on the opposite sides thereof, and sheaves about which said connections pass, of a frame having a narrow base secured to the guide rail structure, a sheave housing formed adjacent the upper part of I said base for receiving said sheave, an offset downwardly presented support toward the bottom thereof, and a bearing web extending from adjacent said housing to adjacent said support, a narrow high-torque electric motor positioned below and secured thereto, a gear carried by the shaft of said motor, a shaft counter to the shaft of said motor mounted in said .web, a large gear carried by said shaft upon one side of said web and enmeshed with the gear upon the motor shaft, and a small sprocket wheel also carried by said shaft and positioned upon the other side of said web, a sprocket wheel of substantially the diameter of a sheave secured thereto, a sprocket chain t co-operating with said sprocket wheels, said frame having a slotted opening ad acent said web to afford clearance for the run of said sprocket chain, said motor and said gears being positioned in their entirety within the space between the vertical plane of said sheave housing and the wall of the shaft, a main electric power line extending adjacent all of said doors, a branch line extending therefrom adjacent each door and connected with the motor adjacent such door, a normally open switch in each of said branch lines adapted to be operated only when a car is positioned adjacent said switch, means carried by and movable with an elevator car co-operating with the switch in any branch line, pole changing switches controllingthe circuits to said main power line, electro-magnetic control mechanisms for said'pole changing switches, and means whereby said control mechanisms may be selectively actuated from a remote point.

In witness whereof I have hereunto affixed my signature this 31st day of March, 1930.

' ROBERT S. PEELLE. 

